Impact assessment of heavy metals pollution of Vartur lake, Bangalore

Abstract

The unscientific disposal of wastes and pollution in urban water bodies has caused immense problems not only to human beings but also to the aquatic biodiversity. Assessment of heavy metals in Vartur Lake, Bangalore, revealed that Cadmium (Cd), Cobalt (Co), Chromium (Cr), Nickel (Ni), and Lead (Pb) all exceeded drinking water standards. Nevertheless, Chromium (Cr) exceeded the CPCB’s tolerance limits for water bodies subjected to effluent discharge. In Eichornia crassipes, Cd, Co, Cr, and Ni were critical. In the sediments, Cadmium (Cd) and Nickel (Ni) exceeded the Probable Effect Level (PEL). Sediment Geo-accumulation Index of the lake showed moderate contamination with Mn, Cu, and Pb. Cr had the highest plant/sediments metal concentration factor even though its bioavailability in plants (71.5 ppm) was lower compared to Manganese (192.3 ppm). This calls for immediate action to be implemented to carry out necessary environmental mitigation measures for the lake.